Step-by-step explanation:
speed = distance/time
speed = 871÷13
speed = 67 mph
distance = speed x time
distance = 67mph X 9hrs
distance = 603 m
Answer:
112.5 mL
Step-by-step explanation:
Let x represent the amount of grape juice to add. Then the total amount of grape juice in the mix is ...
0.15(1800) +x = 0.20(1800+x)
270 +x = 360 + 0.2x . . . . . . eliminate parentheses
0.8x = 90 . . . . . . . . . . . . . . . subtract 270+0.2x
x = 90/0.8 = 112.5 . . . . . . . . divide by the coefficient of x
112 mL of grape juice should be added to make a mix that is 20% grape juice.
<span>The first thing to know is that "an" and "a1" are names with subscripts and are and different from multiplication.
an = a1 + (n-1) d
add -a1 to both sides
an - a1 = a1 - a1 + (n-1) d
</span><span>an - a1 = (n-1) d
</span>d = (an-a1)/(n-1)
